'JavaScript: The Good Parts' by Douglas Crockford is a great place to start[1].

    This authoritative book scrapes away these bad features
    to reveal a subset of JavaScript that's more reliable, 
    readable, and maintainable than the language as a 
    whole-a subset you can use to create truly extensible 
    and efficient code.

The other thing that has had a huge impact on my coding style is learning to write tests for everything with Jasmine[2]. Forcing myself to write tests has basically forced me into better design practices, since it's nigh-on impossible to test javascript callback-spaghetti.

Doing a couple of backbone.js[3] tutorials may be a bit of an eye-opener too.

[1] http://shop.oreilly.com/product/9780596517748.do

[2] http://pivotal.github.com/jasmine/

[3] http://backbonejs.org/